*{
    margin: 0;
    padding: 0;
}
body{
  
    background-image: url(../img/photo.jpg);
    background-repeat: no-repeat;
    background-size: 100% 180%;
    background-position: 0px -50px;
}
h1{
    font-size: 50px;
    text-align: center;
    color: white;
}
#login_box{
    width: 500px;
    height: 300px;
    background-color: #00000068;
    border-radius: 13px;
    margin: auto;
    margin-top: 160px;
    padding-top: 30px;
    text-align: center;
}
#tb_login{
    margin: auto;
    width: 300px;
    /* background-color: blue; */
    color: white;
    
}
#username{
    width: 200px;
    height: 30px;
    margin-top: 20px;
    border-style: none;
    border-bottom: solid 3px white;
    outline: none;
    background-color:transparent
}


#password{
    width: 200px;
    height: 30px;
    margin-top: 20px;
    border-style: none;
    border-bottom: solid 3px white;
    outline: none;
    background-color:transparent

}
#login_btn{
    border: 0;
    width: 150px;
    height: 40px;
    margin-top: 30px;
    border-radius: 20px;
    background-color: plum;
    color: white; /* 修改按钮上文字的颜色 */
    border-radius: 25px; /* 将按钮的左右边框设置为圆弧 */
    background-image: linear-gradient(to right, #00dbde 0%, #fc00ff 100%); /* 为按钮增加渐变颜色 */

}
#login_btn:hover{
    cursor: pointer;
    transition: 0.5s;
    transform: scale(1.1);
 /*    position: relative;
    left: 1px;
    bottom: 1px; */
}

#zhuce_text{
    color: white;
    font-size: 5px;
    margin-left: 320px;
    text-decoration: none;
}
#zhuce_text:hover{
    position: relative;
    left: 1px;
    bottom: 1px;
    color: red;
    border-bottom: 1px solid red;
}


/* 设置input的背景颜色 */
/* 通用 */
::-webkit-input-placeholder { color:white; }
::-moz-placeholder { color:white; } /* firefox 19+ */
:-ms-input-placeholder { color:white; } /* ie */
input:-moz-placeholder { color:white; }